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Post by pistonguy on Jun 9, 2015 11:04:56 GMT -5
Yup.
I jet can't sugar coat this as Iv'e seen Butcher jobs with the mild result in a High speed get offs to grenades on the face of a triple Jump ending with a rider in a Wheelchair.
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Post by geh3333 on Jun 9, 2015 20:40:57 GMT -5
Touching on Polishing. I'll try to explain, excuse the verbiage may not be exacting. On the Intake side we are working with Atomization, it needs to be left scratched up, Polishing will create a surface tension drag of the intake charge. You won't see a head from Mitch Payton to Robert Yates and all in-between with polished Intake Ports Two or Four Stroke. A Shark skin is not Smooth, for it to create incredible bursts of speed it has a rough texture to break the surface tension of the water. If ya just want to make something look pretty with 0 gain polish the exhaust port. Polish the Exhaust port ending with a Jewelers Rouge, She'll be Mirror finish but does "0" That is true . I've also seen this said before . the polishing slows the flow of fuel . its like the fuel sticks to the polished surface . |
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Post by pistonguy on Jun 10, 2015 5:05:20 GMT -5
Touching on Polishing. I'll try to explain, excuse the verbiage may not be exacting. On the Intake side we are working with Atomization, it needs to be left scratched up, Polishing will create a surface tension drag of the intake charge. You won't see a head from Mitch Payton to Robert Yates and all in-between with polished Intake Ports Two or Four Stroke. A Shark skin is not Smooth, for it to create incredible bursts of speed it has a rough texture to break the surface tension of the water. If ya just want to make something look pretty with 0 gain polish the exhaust port. Polish the Exhaust port ending with a Jewelers Rouge, She'll be Mirror finish but does "0" That is true . I've also seen this said before . the polishing slows the flow of fuel . its like the fuel sticks to the polished surface . Bingo, Hit the nail right on the head. Velocity is Very, Very Important, I.m not in much favor of throwing on considerable larger Carb's for the same Velocity reason, The Stocker or just a little larger already Out Flows what the Engine can use. Big Carb, Large Port is like Flushing a Toilet into a Straw. |
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Post by geh3333 on Jun 11, 2015 12:48:50 GMT -5
That is true . I've also seen this said before . the polishing slows the flow of fuel . its like the fuel sticks to the polished surface . Bingo, Hit the nail right on the head. Velocity is Very, Very Important, I.m not in much favor of throwing on considerable larger Carb's for the same Velocity reason, The Stocker or just a little larger already Out Flows what the Engine can use. Big Carb, Large Port is like Flushing a Toilet into a Straw. That's the issue others had also , with bigger carbs. However it seems as if these scoots may be under carbed from the start. I'm only a fan of using a bigger carb if you install a bigger head with bigger intake and exaust ports . also a bigger manifold with a uni filter and a high flow exhaust. If I and others haven't had the success we've had , I would never push installing a bigger carb. But it seems as if these scoots can handle more air and fuel then we first thought. It would be nice to have the equipment to be able to test how much air and fuel these babies can handle, but that would be an expensive test. |
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Post by scooter on Jun 11, 2015 16:06:58 GMT -5
Bingo, Hit the nail right on the head. Velocity is Very, Very Important, I.m not in much favor of throwing on considerable larger Carb's for the same Velocity reason, The Stocker or just a little larger already Out Flows what the Engine can use. Big Carb, Large Port is like Flushing a Toilet into a Straw. That's the issue others had also , with bigger carbs. However it seems as if these scoots may be under carbed from the start. I'm only a fan of using a bigger carb if you install a bigger head with bigger intake and exaust ports . also a bigger manifold with a uni filter and a high flow exhaust. If I and others haven't had the success we've had , I would never push installing a bigger carb. But it seems as if these scoots can handle more air and fuel then we first thought. It would be nice to have the equipment to be able to test how much air and fuel these babies can handle, but that would be an expensive test. It seems a calculable problem. Let's think it through. What are we asking? volume and smallest opening of the carb hole, piston of x size, running at y rpm, something like that? |
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Post by geh3333 on Jun 11, 2015 16:25:01 GMT -5
That's the issue others had also , with bigger carbs. However it seems as if these scoots may be under carbed from the start. I'm only a fan of using a bigger carb if you install a bigger head with bigger intake and exaust ports . also a bigger manifold with a uni filter and a high flow exhaust. If I and others haven't had the success we've had , I would never push installing a bigger carb. But it seems as if these scoots can handle more air and fuel then we first thought. It would be nice to have the equipment to be able to test how much air and fuel these babies can handle, but that would be an expensive test. It seems a calculable problem. Let's think it through. What are we asking? volume and smallest opening of the carb hole, piston of x size, running at y rpm, something like that? We would have to take into consideration manifold , valve size , intake and exhaust size, carb and jet sizes, air filter , head size , carb size . not only that , we would have to compare all of this to a stock carb and a stock bore . we would have to know the suction of the piston . this would vary from scoot to scoot. It would be much harder then it sounds. |
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Post by scooter on Jun 11, 2015 16:31:32 GMT -5
It seems a calculable problem. Let's think it through. What are we asking? volume and smallest opening of the carb hole, piston of x size, running at y rpm, something like that? We would have to take into consideration manifold , valve size , intake and exhaust size, carb and jet sizes, air filter , head size , carb size . not only that , we would have to compare all of this to a stock carb and a stock bore . we would have to know the suction of the piston . this would vary from scoot to scoot. It would be much harder then it sounds. Oh. I thought you were asking how much air and fuel a carb could feed an engine. |
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Post by geh3333 on Jun 11, 2015 16:32:58 GMT -5
This is the thing. I went from close to  + miles per gallon to 60 miles per gallon and I'm not running too rich. That's says a lot . but to calculate how much air and fuel is entering the chamber Well I guess if we had a 1/4 gallon of fuel and ran at a steady rpm until the gas was gone ,we'd be able to see how much fuel was being burned each rotation. So considering these scoots only fire every fourth stroke , maybe it would not be that hard. The only thing is , it would vary from setup to setup. But it will show how much fuel is entering the chamber on each setup. But we won't be able to tell the exact mixture. As long as its not too rich and running good , that would be fine with me. |
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Post by geh3333 on Jun 11, 2015 16:39:09 GMT -5
This is the thing. I went from close to + miles per gallon to 60 miles per gallon and I'm not running too rich. That's says a lot . but to calculate how much air and fuel is entering the chamber Well I guess if we had a 1/4 gallon of fuel and ran at a steady rpm until the gas was gone ,we'd be able to see how much fuel was being burned each rotation. So considering these scoots only fire every fourth stroke , maybe it would not be that hard. The only thing is , it would vary from setup to setup. But it will show how much fuel is entering the chamber on each setup. But we won't be able to tell the exact mixture. As long as its not too rich and running good , that would be fine with me. What this already shows " gas mileage drop " is that these scoots can except more fuel then what is being pulled into the chamber when stock. Think about it . a stock scoot will need.to upjet when switching to a uni and a free flow exhaust. We know more fuel is being burned because the gas milage goes ↓ |
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Post by pistonguy on Jun 12, 2015 17:06:59 GMT -5
Hope we didn't scare Ian the original poster off.
haven't heard from him since it didn't start??
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Post by pistonguy on Jun 12, 2015 17:10:57 GMT -5
It seems a calculable problem. Let's think it through. What are we asking? volume and smallest opening of the carb hole, piston of x size, running at y rpm, something like that? We would have to take into consideration manifold , valve size , intake and exhaust size, carb and jet sizes, air filter , head size , carb size . not only that , we would have to compare all of this to a stock carb and a stock bore . we would have to know the suction of the piston . this would vary from scoot to scoot. It would be much harder then it sounds. There are Formulas and Calculations for this A True Builder and Designer follows these. There is a small number of True Builder Designers in the Country. Most just try to copy there work, or have them do it and Grind there own name in the side of the Cylinder. |
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Post by geh3333 on Jun 12, 2015 18:31:15 GMT -5
I believe scoot was right on. If we each wanted to know how much if being burned in our head and cylinder , all we would need to do is measure a certain amount of fuel out , run it through the scoot at a certain and steady rpm for a certain amount of time . measure how much fuel was used , figure how many ignition strokes were made. Take the amount of fuel used and divide that by the number of ignition strokes, and we should have the amount being burned at each ignition stroke. I think I have that right.
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Post by geh3333 on Jun 12, 2015 18:40:37 GMT -5
Let's say I get 60 miles per gallon . and I ride at a steady 7000 rpms . right now I'm running at 60 mph at 7000 rpms , so I should burn a gallon of gas in 1 hr. The scoot fires every fourth stroke , so we take 60 × 7000 which equals 420,000 rotations in 1 hr. 420000 ÷ 4 equals 105,000 ignition strokes. Now we take the number of ignition strokes and break a gallon down into 105,000 parts which would be ? I'll have to think about this one , lol
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Post by geh3333 on Jun 12, 2015 18:54:15 GMT -5
Ok we have 9.52380952×10(-6) equals. 0.0000095238 gallons per ignition stroke. I, think that's right. .00121 ounces of fuel per ignition stroke. And .0357 ml . man that seems like a small amount .
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Post by geh3333 on Jun 12, 2015 18:57:31 GMT -5
Ok we have 9.52380952×10(-6) equals. 0.0000095238 gallons per ignition stroke. I, think that's right. .00121 ounces of fuel per ignition stroke. And .0357 ml . man that seems like a small amount . So let's times .0357 x 105,000 which would be 3,748.5 ml which would be .99 gallons . so that must be correct. |
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+ miles per gallon to 60 miles per gallon and I'm not running too rich. That's says a lot . but to calculate how much air and fuel is entering the chamber Well I guess if we had a 1/4 gallon of fuel and ran at a steady rpm until the gas was gone ,we'd be able to see how much fuel was being burned each rotation. So considering these scoots only fire every fourth stroke , maybe it would not be that hard. The only thing is , it would vary from setup to setup. But it will show how much fuel is entering the chamber on each setup. But we won't be able to tell the exact mixture. As long as its not too rich and running good , that would be fine with me.